572 MUSCLES. 



Various enzymes have been found in the muscles. To these belong 

 (besides traces of fibrin ferment and myosin ferment?) the catalases and 

 oxidases, which occur only to a slight extent and the glycolytic enzyme 

 (Chapter VII). An amylolytic and a proteolytic enzyme (HEDIN and 

 ROWLAND 1 ) have also been found, and the hydrolytic and oxidizing 

 enzymes (Chapter XIV) active in the formation and destruction of uric 

 acid are also present. 



Extractive Bodies of the Muscles. 



The nitrogenous extractives in the muscles of higher animals con- 

 sist chiefly of creatine and creatinine (especially in fishes) and carnosine. 

 To these also belong inosinic acid (and the closely related carnine), phos- 

 phocarnic acid, carnitine and purine bases, especially hypoxanihine. The 

 purine bases occur partly .free (which is especially the case with hypoxan- 

 thine) and partly combined. 



Among the extractive substances is also found the acid noticed by LIMPRICHT 

 in the flesh of certain cyprinidea, namely, the nitrogenized protic acid, while the 

 isocreatinine found by J. THESBN in fish-flesh is nothing but impure creatinine, 

 according to POULSSON, SCHMIDT and KoRNDORFER. 2 The following have also 

 been found in the muscles, in certain cases only, of a few varieties of animals: 

 uric acid (especially in alligators), taurine (in cephalopoda and oysters), glycocpll 

 (in gasteropoda), betaine and methyl guanidine, in fish meat, several monamino 

 acids and also the three hexone bases histidine, lysine and arginine. 3 Urea occurs 

 in large quantities in the muscle of the shark and ray. The reports are very 

 contradictory in regard to the occurrence of urea in the muscles of higher animals. 

 According to the investigations of KAUFMANN and SCHONDORFF, confirmed by 

 BRUNTON-BLAiKiE, 4 urea is a regular constituent of the muscles, although M. 

 NENCKI and KOWARSKI dispute this. 



In regard to the division of the nitrogenous extractives of the muscles, v. 

 FURTH and SCHWARZ found the following in 1000 grams of the moist extremity 

 musculature of the horse and dog (after subtracting the proteoses derived by 

 secondary cleavage processes), 3.27-3.82 gram extractive nitrogen. Of this 

 4.5-7 per cent was ammonia, 6.1-11.1 per cent purine bodies, 26.5-37.1 per cent 

 creatine and creatinine, 30.3-36.3 per cent carnosine fraction, 8.2-15.3 per cent 

 base residue (carnitine, methylguanidine, etc.) and 6.3-16 per cent urea, poly- 

 peptides and amino-acids. The quantity of purine base nitrogen, according 

 to BURIAN and HALL in fresh meat of the horse, ox and calf, was 0.55 p. m., 0.63 



1 Zeitschr. f. physiol. Chem., 32. 



2 See Limpricht, Annal. d. Chem. u. Pharm., 127, and Thesen, Zeitschr. f . physiol. 

 Chem., 24; Poulsson, Arch. f. exp. Path. u. Pharm., 51; Schmidt and Korndorfer, 

 ibid., 51. 



3 In regard to the extractives of the muscles see besides the specially cited works, 

 Kurkenberg and Wagner, Zeitschr. f. biol. 21; U. Suzuki and collaborators, Zeitschr. f. 

 physiol. Chem. 62 and Chem. Centralbl. 1913, 1; Suwa, Pfluger's Arch. 128 and 129; 

 Zunz, Centralbl. f. Physiol., 18. 



4 Kaufmann, Arch, de Physiol. (5), 6; Schondorff, Pfluger's Arch., 62; Nencki 

 and Kowarski., Arch. f. exp. Path. u. Pharrn., 36; Brunton-Blaikie, Journ. of Physiol., 

 23, Supplement. 



